Shock absorber



Patented sept. v, 193.1 y i i, 2,092,259.

UNITED STATES PATENT OFFICE SHOCK ABSORBER Joseph E. Padgett, Toledo, Ohio. assignor, by

mesne assignments, to General Motors Corporation, Detroit, Mich., a. corporation oi' Delaware Application May 7, 1934, Serial No. 724,318

3 Claims. (Cl. 188-88) This invention relates to shock absorbers and through a shock absorber embodying my invenmore particularly to an improved shock absorber tion; housing. The present invention is an improve- Fig. 2 is a transverse sectional view taken on ment over the shock absorber disclosed in my line 2--2 of Fig. 1; and

5 early Patent No. 1,948,185, issued February 20, Figs. 3 to 10, inclusive, are partial sectional 5 1934. views, which are more or less diagrammatic, show- In explanation of the problem to the solution ing several other constructions for a shock abof which the present invention is directed, I wish sorber housing as contemplated by my invention. to point out that the shock absorber of my earlier Detailed reference will now be made to the acpatent mentioned above is of the type having companying drawings wherein I have shown one 10 housing and cylinder members formed from secform of shock absorber with which the protective tions of metal tubing and, in the use of these means of my invention may be used and have shock absorbers, difficulties have been encounalso illustrated various ways in which the protectered by reason of the housing and, in some intive means may be applied to the shock absorber stances, the housing and cylinder members behOnsing. It Will be Undersilecd. 0f Course, that 15 ing damaged by objects striking the shock abthe invention may be embodied in various other sorber. The housing and cylinder members when types of shock absorbers and that it may assume formed of sections of metal tubing are, in effect, various specific forms other than those herein formed of sheet metal and I have found that by illustrated.

reason of the exposed locations in which these Before prcceeding With the detailed description 20 devices are used on motor vehicles, the sheet metal 0f the invention, I shell describe hriey the shock walls are often subjected to severe blows, from abscrber Which 1S illustrated in Figs. 1 and 2 as stones being thrown up from the road or from being one form of shock absorber with which the other objects, which cause the walls to be bent DrOteiiVe Ineens 0f lny inventicn may be edand distorted or may even puncture'the same, vantageously used. The shock absorber illus- 25 The shock absorbers used on the rear axles of trailed in Figs- 1 and 2 is e direct acting shock vehicles are especially subject to these damaging abscrber Which is vprovided With 2 cylinder barrel blows, by reason of stones or other objects be- I5 and a reservoir barrel or housing IB arranged ing thrown up from the road by the aci-,ion of with a space therebetween forming a fluid chamthe front wheels. ber or reservoir I1. The barrel I5 forms the 30 It is, therefore, an object of the present inven- WOrking Cylinder I3 in Which the piston I9 is 0ption to provide an improved shock absorber haverated by means 0f the piston rOd 20- The cylining a housing embodying means for preventing der and reservoir barrels I5 and I6 are connected damage to the shock absorber by blows delivered and Closed at their ends by means of the closure against the device. plugs 20 and ZI to which the cylinder and reser- 5 Another object of the invention is to provide an AVoir barrels may he Welded, the latter plus having improved shock absorber housing having a guard a bushing 22 therein in Which the piston rod is mounted on the housing and extending along at Siidabieleast a, portion of the Wan there@ The piston of the shock absorber may be pro- A further object of the invention is to provide vided With Openings 23 and lwith a Check Valve 40 an improved shook absorber housing having a, plate 24 having an orice 25 therein, the check laminated wan valve being arranged to restrict the flow of fluid It is also an object of this invention to provide past the piston as the latter moves toward the an improved fluid :dow shock absorber having plug 2 and to further restnct the ow of mud 45 an elongated housing formed from a section of past the piston when the latter moves upwardly toward the plug 2|. The working cylinder is submetal tubing and embodying a guard for the wall su nti n d ti ht t it d i the housing which is also formed from a seca a y m g a s upper en as shown 0 in Fig. 1, and at its lower end has restricted contion of metal tubing and which is coextenslve with nootion with the reservoir through the normally 5 at least a Portion 0f the Wan of the housmg'v open passage or orice 26. This restricted passage 50 Other objects and advantages 0f the inVehtiDh limits the flow-of uid from the cylinder into the will be apparent from the following description reservoir and thus cooperates with the valve 24 when taken in conjunction with the accompanyin resisting the downward travel of the piston u ing sheets of drawings, wherein to render the device double acting.

Fig. 1 is a longitudinal sectional elevation taken The cylinder and reservoir may be charged with the desired amount of resistance fluid, such as oil, through the opening 21, the outer end of which may be closed by the screw plug 29.

Leakage of fluid around the piston rod may be prevented during the operation of the device by a suitable packing 30 provided on the plug 2i and by a leakage collecting chamber 3l provided in this plug just inwardly of the packing. The leakage collecting chamber communicates with the upper end of the reservoir through a return passage 32. l 1 A A connecting eye 33 may be provided onthe outer end of the cylinder rod 29 for connecting the latter with the frame or other part of the vehicle and, if desired, a dust guard 34 may be mounted on this member and arranged to telescope around the shock absorber housing I5.

The shock absorber as thus far described is generally similar to the shock absorber disclosed in my prior patent mentioned above, and when this shock absorber is mounted on a motor vehicle, for example on the rear axle of the vehicle, the device is in a more or less exposed position and the housing formed by the reservoir barrel is subjected to frequent blows by objects which are caused to be thrown up from the surface of the road by the action of the front wheels. I have found that, as the result of such blows, the shock absorber housing may be dented or become bent and, in some instances, even the cylinder barrel i5 may be dented or bent. It may also result in puncturing of the sheet metal housing or leakage of uid at other points.

I have found that the mere thickening of the wall of the housing, as by using a heavy gauge of tubing for forming the wall, does not eliminate this diiculty, but that when the exposed portion of a sheet metal housing of usual thickness is provided with a protective layer or sheath 40 of sheet material, the strength of such portion of the housing and its resistance to bending or denting by stones or other objects striking thereagainst, is increased many times over the resistance to distortion which would be oiered by a 45 wall constituting a single layer. This protective sheath or layer may be arranged in various ways,

some of which have been illustrated in the drawings, and the application of such a sheath to the reservoir barrel of the shock absorber may 50 be regarded as the equivalent of providing the shock absorber with a housing having a laminated wall.

In the shock absorber of Fig. 1 I have shown the sheath or guard 35 as being arranged out- 55 wardly of the reservoir barrel I6 but, obviously,

it could be arranged inwardly of this barrel instead, if it were desirable. The sheath 35 may be formed as a section of sheet metal tubing of approximately the same gauge as the reservoir 60 barrel I6 and when arranged outwardly of the reservoir barrel it may be of a size to telescope around the latter. The sheath 35 may be retained on the reservoir barrel I6 by any suitable means, for example, it may be welded at one or 35 more points to the barrel or to some other available portion of the housing.

It will be understood, of course. that the sheath 35 may be made of suiiicient length to cover and protect that portion of the sheet metal housing 70 which maybe exposed at any time during the operation of the device and, in this instance, I \have shown the sheath extending for a consideriable distance upwardly around the reservoir bar'- rel I6. The dust guard 34 may, if desired, be

avoid interference, the dust guard is preferably provided with an enlarged lower part 39.

In some instances it may be desirable to apply the sheath to certain portions only of the housing of the shock absorber, for example, when the shock absorber is applied to the rear axle it may, in some cases, only be necessary to apply the sheath to the forwardly disposed portion of the shock'absorber housing or, in other words, on that side'of the housing to which the striking objects would normally be directed during the operation of the vehicle. l As an illustration of such an arrangement, I have shown a shock absorber housing 40 in Fig. 3 of the drawings to which such a partial sheath or guard 4I has been applied. The arrangement of Fig. 3 is substantially the same as that illustrated in Fig. 1 with the exception that 'the sheath 4I extends only part way around the shock absorber housing.

Beneficial results may be obtained when the sheath or guard, or at least a portion thereof, is spaced from the surface of the shock absorber housing and, in Fig. 4, I have shown an arrangement of this kind wherein a substantial portion of the length of the sheath 43 is spaced from the outer surface of the wall of the shock absorber housing 44. shown as being tubular so as to extend all the way around the housing 44 and it may be mounted on the shock absorber housing by being provided with a reduced end 45 which is welded or otherwise secured to the housing.

In Fig. 5 of the drawings, I have shown a sheath or guard 46 applied to a shock absorber housing 41 but with the guard extending only part way around the housing. It will be understood, of course, that when such a partial guard is employed it will be mounted on the side of the housing toward which the striking objects would normally be directed during the operation of the vehicle.

In Fig. 6 of the drawings, I have shown a sheath or guard 48 which is generally similar to that of Fig. 4 in that a substantial portion of the length of the guard is spaced from the surface of the shock absorber housing 49. In this arrangement, however, a reduced portion 59 is provided at the upper end of the sheath in addition to the reduced portion 45' at the lower end of the sheath. These reduced portions may be welded or otherwise secured to the housing 49 for mounting the sheath thereon.

Fig. 7 of the drawings shows an arrangement similar to that of Fig. 6 but wherein the sheath 5l is a partial sheath extending only part way around the shock absorber housing 52. The upper and lower ends of this partial sheath may be provided with oilset portions 53 for connecting the sheath with the shock absorber housing and, if desired, the vertical edges of the sheath may also be provided with oiset portions 54 for connection with the shock absorber housing.

In Figs. 8, 9 and 10 of the drawings, I have shown a tubular sheath or guard 55 disposed around a shock absorber housing 56 and wherein means is. provided between the sheath and the housing for spacing the same apart and for connecting the sheath to the housing. In Fig. 8, this interposed connecting means is a ring 51 which may be provided at one or both ends of the sheath. This ring may be formed of metal and may be connected to the sheath and to the shock absorber housing by welding or by any other suitable connection.

In the arrangement of Fig. 9 the interposed In this instance, the sheath 43 is connecting means comprises a ring 58 of rubber or other yieldable material. This ring may be' and the shock absorber housing so that thel sheath will be retained on the latter. If desired, a portion ofthe sheath may be deflected inwardly as by rolling one or more grooves 59 in the outer surface of the sheath whereby the sheath would be locked to the rubber ring and the latter will be tightly pressed against the shock absorber housing.

In Fig. 10 the interposed connecting means between the sheath 55 and the shock absorber housing 56 is a sleeve 60 of resilient material, such as soft vulcanized rubber. The rubber sleeve may be connected to the sheath 55 and to ythe shock absorber housing in any suitable'way. For example, the rubber sleeve may be stretched along the shock absorber housing to reduce its thickness and the sheath 55 then slipped over wardly as by rolling one or more grooves 6I in the sheath similar to the groove 59 shown in Fig. 9.

It will be understood that in the several forms of the invention herein disclosed the sheath or guard embodied in the shock absorber housing increases the strength of the sheet metal wall of the housing, especially with respect .to its resistance to deflection or bending by reason o! stones or other solid bodies being projected thereagainst. This sheath imparts to the sheet metal wall of the housing something of the characteristics of a laminated wall structure with the benecial effect that the wall of the sheet metal housing is especially able to resist accidental blows delivered thereagainst. It will be understood furthermore that the use of a shock absorber housing having a sheet metal wall is very desirable from the standpoint of economy of construction, and the present invention makes possible and practical the use of such an economical sheet metal structure.

While I have illustrated and described the improved shock absorber structure of my invention in a detailed manner it will be understood, of course, that I do not wish to be limited to the precise details of construction and arrangements illustrated and described, but regard my invention as including such changes and modications as do not involve a departure from the spirit of the invention and the scope oi' the appended claims.

Having thus described my invention, I claim:

1. In a shock absorber a housing having a tubular sheet metal wall, a tubular sheet metal member disposed around and coextensive with a portion of said Wall, and a rubber sleeve ex# tending between said member and said wall.

2. In a shock absorber, a housing having a tubular sheet metal wall, a tubular sheet metal sheath disposed around and coextensive with a portion of said wall, forming an annular space between the housing and said sheath; and resilient means filling said space.

3. In a shock absorber, a tubular housing; a

sheath arranged about said housing and spaced therefrom; and a -resllient means lling the space between the housing and sheath.

JOSEPH E. PADGE'IT. 

